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Investigations on the potential natality of various mammalophilic blackflies with special reference to Boophthora erythrocephala De Geer. The potential natality in the different generations of Boophthora erythrocephala showed a considerable variation during the course of the year. The natality was found highest in spring and lowest in July. The increase in autumn did not reach the values observed in spring. The climax in spring was also observed in Odagmia ornata ornata and Wilhelmia lineata. For Boophthora erythrocephala the rate of potential natality varied within different sites of a given running-water-system and from one of these water system to the other. The degree of this fluctuation appears to be different at different parts of the running water. Under special local conditions the potential natality of one population of Boophthora erythrocephala decreased continuously. This was in contrast to other populations of the same area. There was a higher real natality after the uptake of cattle blood than after the uptake of rabbit blood. With increasing physiological age that is with an increasing number of gonotrophic cycles the real and the potential natality decreased. The potential natality was not directly correlated with the body size of the female black flies. Boophthora-populations in which relatively big individuals prevailed did not show a significantly higher potential natality than populations of relatively small Simuliids. In one case the body size increased where as the potential natality decreased. Finally the factors which could possibly influence or govern potential natality are discussed. Zusammenfassung Die potentielle Natalitat von Boophthora erythrocephala schwankte innerhalb eines Jahres zwischen den verschiedenen Generationen relativ stark. Im Fruhjahr war sie am hochsten, im Juli am niedrigsten. Gegen den Herbst nahm die potentielle Natalitat, ohne die Werte der ersten Generation im Fruhjahr zu erreichen, wieder zu. Auch die potentielle Natalitat von Odagmia ornata ornata und Wilhelmia lineata lag im Fruhjahr am hochsten. Innerhalb eines Fliesgewassersystems zeigten die Boophthora-Populationen an verschiedenen Stellen eine zum Teil sehr unterschiedliche potentielle Natalitat, wie dies auch zwischen verschiedenen Systemen beoachtet werden konnte. Die potentielle Natalitat fluktuierte an ein- und derselben Stelle von Jahr zu Jahr. Offenbar fluktuiert sie an den einzelnen Abschnitten auf einem verschieden hohen Niveau. Unter besonderen lokalen Bedingungen nahm die potentielle Natalitat einer Boophthora-Population im Gegensatz zu den benachbarten Populationen fortlaufend ab. Die reale Natalitat war nach der Aufnahme von Rinderblut groser als nach der von Kaninchenblut. Mit zunehmendem physiologischen Alter bzw. mit Zunahme der Anzahl gonotrophischer Zyklen nahmen potentielle und reale Natalitat ab. Die potentielle Natalitat ist nicht unmittelbar von der Korpergrose der weiblichen Mucken abhangig. In einem Falle nahm die Korpergrose zu, wahrend die potentielle Natalitat abnahm. Abschliesend werden einige Uberlegungen zur Analyse des Faktorenkomplexes, der diese potentielle Natalitat beeinflussen bzw. steuern konnte, angestellt.

Neutron transport calculations are needed in many fields of radiation protection and medical physics. Neutron transport is often simulated with a Monte Carlo code, which allows the calculation of neutron dose distributions in different geometries, for example in voxel phantoms. So far little information is available about neutron transport below 15 MeV in tissue-like matter performed with the Monte Carlo code GEANT4. Therefore, we compared GEANT4 results of the ambient dose equivalent for neutron energies from 10 meV to 15 MeV with MCNP results and values published in ICRU 57. The GEANT4 code was found to be appropriate to calculate neutron and photon dose at energies below 15 MeV correctly. Furthermore, a method how to include a dose-assessment factor into the calculation was developed and tested.

The European Commission has funded within its 6th Framework Programme a three-year project (2005–2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organizational framework for this project was provided by the European radiation Dosimetry Group EURADOS. Work Package 6 of CONRAD dealt with “complex mixed radiation fields at workplaces” and in this context it organised a benchmark exercise, which included both measurements and calculations, in a stray radiation field at a high-energy particle accelerator at GSI, Germany. The aim was to intercompare the response of several types of active detectors and passive dosemeters in a well-characterised workplace field. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers are discussed in Rollet et al. (2008) and in Wiegel et al. (2008). This paper focuses on the intercomparison of the response of the dosemeters in terms of ambient dose equivalent. The paper describes in detail the detectors employed in the experiment, followed by a discussion of the results. A comparison is also made with the H*(10) values predicted by the Monte Carlo simulations and those measured by the BSS systems.

The response functions of a Bonner sphere spectrometer with gold activation foils as thermal neutron detectors were calculated with GEANT4. The spectrometer includes 15 polyethylene spheres with diameters between 1.3 and 15 in. and a bare gold foil. By comparison with results of MCNPX calculations, the neutron transport in GEANT4 was first extensively verified. In addition, the calculation method, which includes folding the neutron flux at the location of the gold foil with the neutron capture cross-section of gold, was tested in detail. The agreement between the GEANT4 and the MCNPX calculations was reasonable, and a complete set of Bonner sphere functions was calculated with GEANT4.

A new electronic meter for personal radon exposures was developed and several prototypes were built. The exposure meter is optimized with respect to short-term (days) and long-term ( > 1 y ) measurements of indoor radon concentrations and personal radon exposure. The exposure meter records measured concentration levels in adjustable time intervals allowing a time resolved analysis.

Electronic personal neutron dosimeters developed at GSF, PTB, and LMU, were exposed with mono-energetic neutrons at the PTB neutron irradiation facility in Braunschweig, Germany. The neutron energies used ranged from 1.5 to 4.1 MeV. The doses measured by each dosimeter were compared to each other and to the Saphydose-n dosimeter that is commercially available. All dosimeters were calibrated based on either 252 Cf and/or 241 Am–Be neutron sources or a 60 Co secondary standard reference field. The doses measured were compared to estimates of reference values based on a long counter. Generally, all dosimeters produced reasonable results, given the uncertainties involved. It was noticed that the dosimeter responses show slight dependencies on energy. The corresponding differences are summarised and discussed.

A Bonner multi-sphere spectrometer has been installed in 2005 at the Environmental Research Station 'Schneefernerhaus' (2660 m above sea level) on the Zugspitze mountain, Germany, to measure the energy spectrum of cosmic-ray neutrons at high altitudes continuously. The system can be used to investigate small temporal variations in the cosmic radiation intensity. For example, measurements were done during periods of 2 Forbush decreases of the cosmic radiation intensity in July and September 2005, respectively. The results were compared with those obtained by using neutron monitors, and neutron fluence spectra measured during these events are presented and discussed.

International audience; In 2011 a measurement intercomparison was launched by EURADOS WG7, with the objective of providing the participants with the tools to calibrate their detection systems for detection of 241Am in the skull bone, and evaluate the variability due to the used of the different calibration phantoms. Three skull phantoms were used in this intercomparison the USTUR Case 0102 skull phantom, the BfS skull phantom and the CSR skull phantom. Very good agreement was found between the results of the twelve participating laboratories, with relative deviations of less than 15% for the BfS phantom and less than 17% for the USTUR phantom when measurement efficiency in defined positions was compared. However, the phantoms' measured absolute 241Am activities showed discrepancies of up to a factor of 3.4. This is mainly due to the physical differences between the standard calibration phantoms used by the participants and those used in this intercomparison exercise. © 2015 Elsevier Ltd. All rights reserved.

Detailed characterization and classification of precipitation is an important task in atmospheric research. Line scanning 2-D-video disdrometer technique is well established for rain observations. The two orthogonal views taken of each hydrometeor passing the sensitive area of the instrument qualify this technique especially for detailed characterization of non symmetric solid hydrometeors. However, in case of solid precipitation problems related to the matching algorithm have to be considered and the user must be aware of the limited spacial resolution when size and shape descriptors are analyzed. This work has the aim of clarifying the potential of 2-D-video disdrometer technique in deriving size, velocity and shape parameters from single recorded pictures. The need of implementing a matching algorithm suitable for mixed and solid phase precipitation is highlighted as an essential step in data evaluation. For this purpose simple reproducible experiments with solid steel spheres and irregularly shaped styrofoam particles are conducted. Self-consistency of shape parameter measurements is tested in 40 cases of real snow fall. As result it was found, that reliable size and shape characterization with a relative standard deviation of less than 5% is only possible for particles larger than 1 mm. For particles between 0.5 and 1.0 mm the relative standard deviation can grow up to 22% for the volume, 17% for size parameters and 14% for shape descriptors. Testing the adapted matching algorithm with a reproducible experiment with styrofoam particles a mismatch probability of less than 2.5% was found. For shape parameter measurements in case of real solid phase precipitation the 2DVD shows self-consistent behavior.

This work compares the results of four different unfolding codes, MSANDB, MAXED, FRUIT and BONMA, which are based on different unfolding techniques. Additionally, Bayesian parameter estimation is also considered. All unfolding codes were supplied with the same set of input data acquired at the Environmental Research Station 'Schneefernerhaus' on the Zugspitze mountain, corresponding to continuous measurements of secondary neutrons from cosmic radiation. The HMGU high-energy extended Bonner sphere spectrometer (BSS), consisting of 16 measuring channels with (3)He proportional counters, was used as a reference BSS. The differences in the neutron spectra obtained with the different unfolding codes are discussed, and the uncertainties of integral quantities, like neutron fluence and ambient dose equivalent, are quantified.

For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m(-3) Radon atmosphere or by a 15 Bq m(-3) Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres.

In this paper, a method is presented which permits the assessment of 241 Am activities in the skull or in the whole skeleton. The method is based on a calibration procedure using a flat calibration source, and does not require the use of human skull phantoms. The method was, however, previously tested using two skull phantoms with a known 241 Am activity. One of the skull phantoms, which was made available by the US Transuranium Registry, was developed on the basis of a real contamination case. The other skull phantom was produced on the basis of a human skull which was artificially contaminated with 241 Am. The calibration method using the flat 241 Am source was then applied to a living individual who had been contaminated about 25 years previously A 241 Am skeleton activity is given for this individual, and compared to the results obtained using the skull phantoms.

Two examples of individual dose assessment of workers in special monitoring programs are presented, a uranium and an americium incorporation case. It is demonstrated that careful model modifications lead to better dose estimates but that in many cases an optimisation of parameters is not necessary to get a reliable assessment of the committed effective dose. In some cases the use of individual SEE values might be more sensitive with regard to the committed effective dose than very sophisticated modifications of biokinetic models.

Artificial substrates and histological staining procedures have been used to study interference effects among blackfly larvae. Colonising larvae apply silk to the substratum to attach themselves for filter feeding, locomotion or pupation. We have hypothesised that species might react differently to alterations of the substratum caused by the silk of previously colonisers and have therefore compared Simulium noelleri FRIEDERICHS and Simulium vernum MACQUART, which are characteristic of different habitats. The number of larval colonisers and the number and position of their silk pads on previously colonised and new control substrates were recorded after 24h of exposure in streams. The results support our hypothesis that blackfly species react to surface properties differently and are thus affected differently by previous colonisers. Whereas S. noelleri seems to prefer previously colonised substrates or, at least, is not negatively affected by silk remnants on the surfaces, S. vernum appears to avoid areas covered by the silk of other larvae. We conclude that interference caused by silk remnants and species-specific differences in tolerance concerning surface properties affect simuliid density, distribution and colonisation dynamics.

An einigen Beispielen (u. a.Simulium costatum, S. nolleri, S. ornatum undProsimulium tomosvaryi) wird die spezifische Auswahl von Eiablageplatzen durch die Simuliidenweibchen belegt. Diese Weibchen reagieren auf Umweltveranderungen im Bereich der Fliesgewasser, sei es durch die Gewasserdynamik, sei es durch Eingriffe des Menschen, unmittelbar. Ohne wesentliche Veranderungen in und an den Fliesgewassern bleibt das jeweilige Artenspektrum uber einen langen Zeitraum weitgehend erhalten. Offenbar stellen Signalfaktoren an Strukturen des Habitats bzw. Subhabitats gebunden bei der proximaten Habitatselektion die Orientierung und artspezifische Auswahl sicher. Diese Weibchen besitzen ein ultimat erworbenes Habitatschema. Fehlen bestimmte Signale (Merkmale) werden die Eiablageplatze nicht erkannt und die Besiedlung uber die Eiablage unterbleibt.

A new partial body counter has been installed and calibrated at the Institute of Radiation Hygiene of the Federal Office for Radiation Protection, Munich, Bavaria. The system is especially designed for radionuclides emitting low energy photons such as241 Am and210Pb. In addition, thorium, uranium and daughter products,60Co,137Cs and40K can be detected. The main components of the system are a shielding chamber, 4 high purity low-energy germanium detectors with beryllium windows and the corresponding electronics and software. A LLNL Realistic Phantom is used to calibrate the system. Inactive organs and organs loaded with a known amount of241Am (right lung, left lung, liver) are available to quantify the response of each detector separately. Detector efficiencies are given as function of chest wall thickness (1.7 to 3.4 cm). Lower limits of detection for241Am using a measurement time of 3600 seconds are 6, 7 and 7 Bq for right lung, left lung and liver, respectively. In order to estimate skeleton activities, a skull phantom loaded with241Am is available. For one detector, the lower limit of detection for the skull is 2 Bq.

Since 1987, 134Cs and 137Cs activities have been measured in about 250 soil samples and about 350 samples of different fungal species grown in a coniferous forest in Bavaria, Germany. Variations of 137 Cs 134 Cs ratios are less than 10% within samples from the same soil horizon and year. Similarly, 137 Cs 134 Cs ratios vary within less than 10% in mushroom samples of the same species and year. In contrast, the specific activities of 134Cs and 137Cs in soil samples of the same horizon and in mushroom samples of the same species vary by up to one order of magnitude. Two approaches are presented to estimate mycelium location of fungi. In the static approach, 137 Cs 134 Cs ratios in soil and mushrooms, corrected to May 1986 and averaged over 1987–1994, are analysed. These ratios range from 1.74 ± 0.06 in the L-horizon to 2.41 ± 0.46 in the B-horizon. The corresponding ratios measured in 14 fungal species vary between 1.73 ± 0.12 (Lepista nebularis) and 2.16 ± 0.26 (Russula cyanoxantha). By comparing these ratios, information on the major mycelium location can be gained. In the dynamic approach, the change with time of the 137 Cs 134 Cs ratio in 14 fungal species and in different layers of forest soil is compared. At the investigated site, both approaches yield similar results. The advantages of both methods are discussed.

Caesium-134 and 137 Cs measurements in about 250 samples from L-, Of-, Oh-, Ah- and B-horizons of a Bavarian forest from 1987 to 1994 are analysed with respect to migration by using a compartment model. The derived ecological half-lives are 2.8 years, 3.8 years, 4.4 years and 7.7 years, respectively. By using these results, caesium behaviour can be predicted for about 25 years. The resulting profile is similar to that found nowadays for weapons fallout caesium, migrating within about 25 years in the same forest. Therefore, the model is suitable for the estimation of future behaviour of radiocaesium in the forest investigated for a period of about 25 years after deposition.

In the framework of the EC-coordinated research program of ECP-5, the behaviour of radionuclides in natural and seminatural ecosystems was investigated. The main work is focussed on the transfer of radionuclides from soil to plants of the understorey vegetation. Therefore soil and plant samples from three sites in the 30-km zone around Chernobyl were analysed radiochemically for Pu and Sr and by γ-spectrometry for Cs, Ce, Ru, Eu, Sb and other longliving radionuclides. Based on these data, transfer factors of the above-mentioned radionuclides by different plants on different soils with varying properties were determined. The transfer factor is defined as ratio of the specific activity in plants to the specific activity in organic horizons. The specific activities of plutonium in plants are generally low with transfer factors in the range of 0.001 –.02, but increase to 0.3 in berries. Radiostrontium shows an average transfer factor of 0.2 and is about the same for all plants and sites, whereas the greatest variance in transfer factors is observed for radiocaesium. Depending upon soil type and plant species, the values range from 0.03 in a fern up to 16.7 in a mushroom. For cerium, a 3-valent ion with generally low uptake by plants, unexpectedly high values ranging up to a transfer factor of 0.43 were measured. For other fission products such as ruthenium, antimony, europium and the activation product, cobalt, low transfer factors in the range of 0.001 – 0.01 were determined. These radionuclides are obviously not accumulated by plants.

Essential presumptions for the building of centres of plague and damage inducing Simuliid species are the species specific monotop, the habitat selection, the habitat structures, and the habitat preferences of the populations in their connection to the potency of species and valency of factors. The decisive structural elements for the abundance dynamics are the mortality of the preimaginal stages, the potential natality of the adults, their gonotrophie cycles, and the number of generations. Larval mortality, the potential natality of adults and the number of generations of plurivoltine species are key factors effecting intra- and interannual population changes considerably in both up and down directions. Egg mortality determines mainly the oscillations. On fluctuations it acts only under the influence of additional environmental conditions because of the compensation by the potential natality. The pupal stage is stable. The regulation of the population dynamics originates from running waters. Temperature, nutrient availability, and substrates are important factors of requisites respectively. Damages by Simuliids cannot be led back directly to abundance dynamics but they are to be infered from these dynamics. By this abundance dynamics the potential of individuals is provides on which environmentally directed accumulative processes and concentrating processes can act on different level of the individual development of blackflies. Climate and weather changes with decreasing and increasing effects and their influence on coincidences favour to progress of damage or are its presumption. These effects act on the day rhythm of the approach flight of the blackfly females, their landing density and biting intensity at the hosts. The weather dependent time when the cattle are first sent to pasture and the sensibility of grazing animals changing with exposition time, are variable dimensions in space and time. The sensibility may change into a pre-immunity that lasts over the whole vegetation period. The behaviour of the grazer and that of the temporary ectoparasites influence the plague induction and possible illness of the host individuals. Because of the numerous variables no long-time prognosis about the occurrence of damages is possible. The probable historical development of the population and abundance dynamics from the original conditions to the modification of running waters under the influence of man in the cultural landscape and its design is outlined.

In this paper measurements of the radionuclides of 36Cl, 41Ca, 60Co, 152Eu and 154Eu in samples from Hiroshima, which were exposed to neutrons of the A-bomb explosion, are interpreted. In order to calculate the neutron spectrum at the sample site, neutron transport calculations using Monte Carlo techniques were carried out. Activation profiles in a granite mock-up irradiated with reactor neutrons could be reproduced by this method using DS86 input parameters. The calculated neutron spectrum at the sample site for non-thermal neutrons is identical to that obtained in DS86, but contains some 50% more thermal neutrons. The influence of parameters like soil composition, source terms and air humidity on the activation of these radioisotopes is discussed. The granite-covered earth at the sample site, for example, hardens the spectrum in comparison with DS86 values. Even when using a fission spectrum pointing downward and neglecting air humidity one cannot explain our 36Cl measurements. If the effective thermal neutron fluences, that have a similar ratio of resonance integral to thermal neutron capture cross sections obtained from 36Cl, 41Ca and 152Eu, are averaged, a bomb yield of about 16 kt is deduced in agreement with a bomb yield of (15 +/- 3) kt estimated in DS86.

[1] Two Bonner Sphere Spectrometers (BSS) were used – one at the Schneefernerhaus, Germany (altitude: 2650 m; geomagnetic cut-off: 4.1 GV), the other at the Koldewey station on Spitsbergen (sea level; geomagnetic: cut-off 0 GV) – to measure continuously the spectral flux distribution of secondary neutrons from cosmic radiation. At the Schneefernerhaus, the flux of thermal neutrons was about 75% higher in summer than in winter, that of epithermal neutrons about 80%, that of neutrons between 0.125 and 17.8 MeV about 32%, and that of neutrons above 17.8 MeV about 4%, respectively. The period of the observed oscillations was very close to one year. Similar oscillations were observed at the Koldewey station, with somewhat smaller amplitudes (40%, 45%, 22%, and 2%, respectively). At both stations, the flux of the neutrons above 17.8 MeV increased with time similar to the count rates measured by nearby neutron monitors. While this increase reflects changes in the Sun's activity, the observed oscillations are due to changes in ground albedo neutrons and their absorption due to snow. Consequently, the monthly averaged neutron ambient dose equivalent rates, H*(10), oscillated by about ±7% at the UFS and about ±4% at the Koldewey Station. The results demonstrate that BSS measurements could be used to monitor secondary neutrons from cosmic radiation above about 20 MeV. Below detailed neutron transport calculations are necessary to correct for changes in ground albedo neutrons and snow cover. The data presented here can be used as an experimental basis to perform such simulations.

An enriched 58 Ni sample has been irradiated with thermal neutrons together with an enriched 54 Fe target. After chemical purification of the nickel sample, the produced radioactivities of 59 Ni and 55 Fe were measured with a silicon detector. The half-life of 59 Ni has been deduced to be 108,000 ± 13,000 years. This halflife is larger than the commonly adopted half-life value of 76,000 ± 5000 years but is in full agreement with 59 Ni concentration and activity measurements of the meteorite Admire. With accelerator mass spectrometry, the cross-section of the reaction 60 Ni(n,2n) 59 Ni for 14.8 MeV neutrons has been measured to be 410 ± 100 mb.

The active radon exposure meter developed recently at the German Research Center for Environmental Health (Helmholtz Zentrum Munchen) was used to measure radon concentrations in 12 tombs located in the Valley of the Kings, Egypt. Radon concentrations in air between 50 ± 7 and 12 100 ± 600 Bq m(-3) were obtained. The device was also used to measure individual radon exposures of those persons working as safeguards inside the tombs. For a measurement time of 2-3 d, typical individual radon exposures ranged from 1800 ± 400 to 240 000 ± 13 000 Bq h m(-3), depending on the duration of measurement and radon concentration in the different tombs. Based on current ICRP dose conversion conventions for workers and on equilibrium factors published in the literature for these tombs, individual effective dose rates that range from 1.5 ± 0.3 to 860 ± 50 µSv d(-1) were estimated. If it is assumed that the climatic conditions present at the measurement campaign persist for about half a year, in this area, then effective doses up to ∼ 66 mSv could be estimated for half a year, for some of the safeguards of tombs where F-values were known. To reduce the exposure of the safeguards, some recommendations are proposed.

Wet and, to a lesser extent, dry deposition of atmospheric (129)I are known to represent the dominating processes responsible for (129)I in continental environmental samples that are remote from (129)I sources and not directly influenced by any liquid (129)I release of nuclear installations. Up to now, however, little is known about the major emitters and the related global deposition pattern of (129)I. In this work an overview over major sources of (129)I is given, and hitherto unknown time-dependent releases from these were estimated. Total gaseous (129)I releases from the US and former Soviet reprocessing facilities Hanford, Savannah River, Mayak, Seversk and Zheleznogorsk were found to have been 0.53, 0.27, 1.05, 0.23 and 0.14TBq, respectively. These facilities were thus identified as major airborne (129)I emitters. The global deposition pattern due to the (129)I released, depending on geographic latitude and longitude, and on time was studied using a box model describing the global atmospheric transport and deposition of (129)I. The model predictions are compared to (129)I concentrations measured by means of Accelerator Mass Spectrometry (AMS) in water samples that were collected from various lakes in Asia, Africa, America and New Zealand, and to published values. As a result, both pattern and temporal evolution of (129)I deposition values measured in and calculated for different types of environmental samples are, in general, in good agreement. This supports our estimate on atmospheric (129)I releases and the considered substantial transport and deposition mechanisms in our model calculations.

For the first time a depth profile of the radioisotope41Ca produced by neutrons from the atomic bomb explosion of Hiroshima was measured. The measurements were performed at the Munich Tandem Laboratory via accelerator mass spectrometry. The41Ca depth profile is part of the evaluation to determine the neutron spectrum of the A-bomb which is basis of the Dosimetry System 1986.

Pupae of Simulium noelleri Friederichs, 1920 were reared in an artificial stream at water temperatures of 6, 11, 16, 21, 26 and 30 °C. Pupation and eclosion rates and eclosion rhythmics were determined. Pupal development of S. noelleri is among the fastest found in Simuliids. It ranges from a mean value of 25 days at 6 °C to 2–3 days at 21 °C and higher. Pupation and adult eclosion are increasingly synchronized with rising temperatures. Eclosion rhythmics showed peaks at 12.00 and 20.00 h with 6, 21 and 26 °C, but peaks at 12.00 and 16.00 h with 11 and 16 °C, which remains largely unexplained. Mortality decreases above 11 °C with 10–20%. Comparatively high pupation and eclosion rates at temperatures above 11 °C indicate warm stenothermous adaptation of S. noelleri. Development at low temperatures shows high ecological potency towards wide temperature ranges. These results are important for the understanding of habitat-dependence. Zusammenfassung Zur Wirkung der Temperatur auf die Puppenentwicklung bei der autogenen und stenotopen Kriebelmucke Simulium noelleri Friederichs, 1920 (Dipt., Simuliidae) Puppen von Simulium noelleri Friederichs, 1920 wurden in einer Fliesrinne bei Wassertemperaturen von 6, 11, 16, 21, 26 und 30 °C zur Entwicklung gebracht. Verpuppungs- und Schlupfraten sowie die Schlupfrhythmik wurden bestimmt. Die Puppenentwicklung von S. noelleri ist eine der schnellsten unter den Simuliiden. Sie reicht von einem mittleren Wert von 25 Tagen bei 6 °C bis zu 2-3 Tagen bei 21 °C und hoher. Verpuppung und Schlupf der Imagines werden mit steigenden Temperaturen zunehmend synchronisiert. Die Schlupfrhythmik der Imagines zeigt Maxima um 12.00 und 20.00 Uhr bei 6, 21 und 26 °C, dagegen um 12.00 und 16.00 Uhr bei 11 und 16 °C, was weitgehend unerklart bleibt. Die Puppenmortalitat sinkt bei Temperaturen oberhalb 11 °C um 10-20%. Vergleichsweise hohe Verpuppungs- und Schlupfraten bei Temperaturen oberhalb 11 °C deuten auf eine warm-stenotherme Adaption von S. noelleri hin. Entwicklung bei niedrigen Temperaturen zeigt eine hohe okologische Potenz bezuglich weiter Temperaturbereiche. Die Ergebnisse dieser Arbeit sind von Bedeutung fur das Verstandnis der Habitat-Bindung.

The radiation field at flight altitudes is generated by the interaction of the primary cosmic radiation from space with atoms of the atmosphere. The cosmic particle flux is significantly higher on board aircraft than at the ground level and its intensity depends on latitude, altitude, solar activity and solar eruptions. Owing to the complexity of the field of secondary cosmic radiation—in fact this field consists of a variety of different particles including neutrons, protons, electrons, positrons, photons, positive and negative muons, etc., with kinetic energies exceeding the GeV range—there is no dosemeter system available so far that is able to cover the dose contributions of these particles separately.

Two Bonner sphere spectrometers (BSSs) have recently been installed to measure secondary neutrons from cosmic radiation continuously, one at the environmental research station 'Schneefernerhaus' at an altitude of 2650 m in Germany and the other at the Koldewey station close to the North Pole in Ny-Alesund, Spitsbergen. After unfolding, both systems provide neutron fluence energy distributions as a function of time. Based on these distributions and on fluence-to-dose conversion coefficients, mean ambient dose equivalent rate values of 75.0 +/- 2.9 nSv h(-1) and 8.7 +/- 0.6 nSv h(-1) were obtained for October 2008, respectively (quoted uncertainties represent standard deviations of 124 values obtained during the measurement period). Ambient dose equivalent rates measured by means of an extended rem counter at the Schneefernerhaus agree with those based on the BSS neutron energy distributions within 5 %. The ambient dose equivalent rate was also calculated based on simulated FLUKA neutron energy distributions in the atmosphere. Even without detailed modelling of the local environment, an agreement better than 30 % was obtained between the ambient dose equivalent rate based on the FLUKA distributions and those based on the BSS measurements at the Schneefernerhaus, for neutrons above about 20 MeV. This agreement is expected to be even better if the influence of the local environment on the measured neutron fluence energy distribution will be calculated.

The assessment of the exposure to cosmic radiation onboard aircraft is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher onboard aircraft than at ground level and its intensity depends on the solar activity. The dose is usually estimated using codes validated by the experimental data. In this paper, a comparison of various codes is presented, some of them are used routinely, to assess the dose received by the aircraft crew caused by the galactic cosmic radiation. Results are provided for periods close to solar maximum and minimum and for selected flights covering major commercial routes in the world. The overall agreement between the codes, particularly for those routinely used for aircraft crew dosimetry, was better than ±20% from the median in all but two cases. The agreement within the codes is considered to be fully satisfactory for radiation protection purposes. © The Author 2009. Published by Oxford University Press. All rights reserved.

EPCARD.Net as completely new code is based on the same approved physical algorithm as EPCARD version 3.34. As a major feature, many significant changes were made in the information technology area. There are only a few physical improvements adopted in the parameters database of the new EPCARD.Net. These are mainly 'dynamic' fluence-to-dose conversion coefficients and the most recent model of the world grid cut-off rigidity. Differences between EPCARD.Net and EPCARD version 3.34 are discussed in terms of effective dose. These differences turned out to be less than approximately 8 %.

The neutron and photon absorbed dose distribution of the FRM II neutron beam was calculated using GEANT4 inside a Voxel phantom. As input of these calculations, the measured primary neutron spectrum at the patient treatment position and a simulated photon spectrum was used. It was demonstrated that any RBE-energy data can be used, to calculate 3-dimensional distributions of the biologically weighted dose from the corresponding absorbed doses.

In dieser Arbeit werden insbesondere die fur die Habitatselektion bzw. Habitatbindung praimaginaler Simuliidae wesentlichen Prozesse der Drift und Substratbesiedlung analysiert. Unter Berucksichtigung eigener Ergebnisse und des Schrifttums werden die Verhaltensweisen der Larven in den verschiedenen Phasen (Zudrift, Landung, Migration, Nahrungsaufnahme, Hautung, Kokonbau) dargestellt und die sie beeinflussenden Faktoren genannt. Hervorgehobene Widerspruche und Probleme sollen auf mogliche Neuansatze und Wege der weiterfuhrenden Analyse hinweisen. Erkenntnisse fur die Praxis, wie z. B. die Notwendigkeit der Trennung von primarer und sekundarer Dispersion, die bei der Erfassung von Dispersionen und Praferenzen zu berucksichtigen ist, werden erortert. Mogliche Storgrosen, wie z.B. Migration, Sekretalterung oder Interferenz, werden als Abdrift auslosender Larven bzw. Adhasion und andere Substrateigenschaften werden auf ihre Funktion als driftbeendende Faktoren uberpruft.

Dose assessment procedures for cosmic radiation exposure of aircraft crew have been introduced in most European countries according to the corresponding European directive and national regulations (1). The radiation exposure due to solar particle events is still a matter of scientific research (2). Several in-flight measurements were performed during solar storm conditions. First models to estimate the exposure due to solar particle events have been discussed. Recently EURADOS (European Radiation Dosimetry Group, http://www.eurados.org/) has started to coordinate research activities in model improvements for dose assessment of solar particle events. This paper describes the outline and preliminary results of a work package related to the European project CONRAD (Coordinated Network for Radiation Dosimetry) on complex mixed radiation fields at working places. The major aim of a subgroup of that work package is the validation of models for dose assessment of solar particle events, using data from neutron ground level monitors, in-flight measurement results obtained during a solar particle event and proton satellite data.

The radioisotope 41 Ca produced by the Hiroshima A-bomb in a gravestone 107 m from the hypocenter was measured with accelerator mass spectrometry (AMS) at the Munich accelerator laboratory. The resonance integral for the reaction 40 Ca(n,γ) 41 Ca was determined to be I γ = (0.22 ± 0.02) b. This, together with γ spectrometric data on 60 Co, 152 Eu and 154 Eu and AMS data on 36 Cl from the same gravestone permitted deduction of the neutron energy spectrum and fluence at this distance in Hiroshima. The derived spectrum is much harder than the spectrum used in the Dosimetry System 1986, DS86.

The detection system of accelerator mass spectrometry (AMS) with completely stripped ions of 26Al, 36Cl, 41Ca and 59Ni at the Munich accelerator laboratory and measurements with these ions are presented. Detection limits are given. The presented applications are: dating of groundwater of the Milk River aquifer and deduction of the neutron fluence and spectrum of the Hiroshima A-bomb.

Estimates of (129)I depositions from (129)I releases of reprocessing plants are so far based on measurements of soil and rain water samples. Because (129)I concentrations in these samples show a highly temporal and spatial variability, the (129)I deposition values deduced from single measurements cannot be seen as representative for a larger area. Here it is proposed to use lake water as an archive for former (129)I depositions, to overcome these limitations. If the limnological parameters of any lake are known, the local (129)I deposition flux can be deduced which is temporally averaged over the flushing time, and spatially averaged over the catchment area of the lake. Samples were collected from various European lakes and from Lake Baikal (Russia). The (129)I concentration in these samples was measured by means of accelerator mass spectrometry, and values between 0.3 and 8.1x10(8) at/l were obtained. Deduced (129)I deposition fluxes averaged over the flushing times of the lakes range from 0.3 to 9.3x10(12) at/m(2) y. The (129)I deposition fluence measured for Lake Baikal is attributed predominantly to releases from the former Soviet reprocessing facilities Chelyabinsk, Tomsk and Krasnoyarsk, while the (129)I deposition fluxes deduced for all other lakes are attributed to releases from the European reprocessing activities at Sellafield, Marcoule and La Hague.

The fall-out of cosmogenic 36Cl was determined by measuring the 36 Cl Cl ratios in old wines from the Rheingau in Germany [1]. The measured 36Cl/Cl ratios from the prebomb samples were compared with the sun spot numbers which are correlated to the solar cycle. A correlation between the sun spot number and the 36 Cl Cl ratios in the samples could not yet be confirmed.

Fur Erfolgskontrollen nach Bekampfungsmasnahmen gegen Kriebelmuckenlarven in Fliesgewassern mit Larviziden bzw.Bacillus thuringiensis var.israelensis wird der Einsatz kunstlicher Substrate empfohlen. Es wird ein Versuchsplan aufgestellt (u. a. Vorversuche, Anzahl der Substrate pro Probe, Zeitplan, Auswertung) und auf die Fakten hingewiesen, die beachtet werden mussen, um eine einwandfreie Erfolgskontrolle zu gewahrleisten. Von verschiedenen Autoren empfohlene Kontrollverfahren werden mit dem Einsatz kunstlicher Substrate unter Berucksichtigung der vorgeschlagenen Versuchanordnung und-planung kritisch verglichen.

Der kontinuierliche Prozes des Anfluges, der Landung und der Blutaufnahme der Kriebelmucken an bzw. auf dem Wirt wird in einzelne Verhaltensfelder gegliedert und diese begrifflich getrennt (z. B. in Anflugdichte, Anflugaktivitat, Landeaktivitat). Zwischen den einzelnen Feldern wird eine Hierarchie von Teilpopulationen sichtbar, deren formale Bezuge zueinander festgelegt werden. Zahlreiche verschiedene Umwelteinflusse greifen in die Verhaltensfelder unterschiedlich ein und beeinflussen sowohl einzelne Sequenzen als auch den gesamten Ablauf der Verhaltensaktivitaten. So ist nicht zu erwarten, das sich zwischen den einzelnen aktiven Teilpopulationen, die einander hierarchisch folgen, situativ ein stabiles numerisches Verhaltnis einspielt und beispielsweise die Anzahl landender Mucken weitgehend derjenigen der blutaufnehmenden entsprache. Durch die Erfassung von Teilpopulationen bestimmter Aktivitaten kann nicht unmittelbar auf die ubergeordneten Teilpopulationen bis hin zur Populationsgrose — oder umgekehrt — geschlossen werden.

Es wird von einem im Jahresverlauf spaten Schadfall bei Weidetieren (5 tote, 6 schwer erkrankte Rinder) berichtet, der durch zahlreiche Stiche vonBoophthora erythrocephala verursacht wurde. Entsprechende Folgerungen fur die Praxis werden aus dem Schadfall abgeleitet. Das Zustandekommen von Schadfallen durch Kriebelmucken wird durch das Zusammenwirken von realer Abundanz als Basis, umweltgesteuerten Akkumulationseffekten und dem unterschiedlichen Grad der Empfindlichkeit erstmals bzw. frisch aufgetriebener Weidetiere, deren Anteil an der Gesamtpopulation wie der zeitlichen Abfolge des Auftriebes erklart. Auf die Bedeutung des Situativen im Zusammenwirken und Auftreten der einzelnen Faktoren und Ereignisse beim Zustandekommen von Schadfallen wird hingewiesen.

Die Speicheldrusen adulter Kriebelmucken (Boophthora erythrocephalaDe Geer, Simuliidae, Diptera) wurden vor und nach Blutaufnahme elektronenmikroskopisch untersucht. Die Zellen von Haupt-und Nebendrusen unterscheiden sich in ihrer Feinstruktur deutlich. Die Kerne der grosen Hauptdrusenzellen enthalten im Gegensatz zu den kleineren der Nebendrusenzellen Riesenchromosomen. Die Produktion von mindestens zwei verschiedenen Sekretsubstanzen wird angenommen: stark elektronendichtes Material in der Hauptdruse, deutlich weniger dichtes in der Nebendruse. Die Ausbildung eines in beiden Drusenabschnitten reich entwickelten granularen endoplasmatischen Reticulums last darauf schliesen, das es sich dabei um Proteine handelt.

The genus Cylindrocorpus Goodey, 1939 is divided into two subgenera Cylindrocorpus subg. nov. with paired female gonads and Protocylindrocorpus subg. nov. with a single gonad. Diagnoses are made and Cylindrocorpus (Protocylindrocorpus) goodeyi n. sp. is described. A diagnostic key to all the species of Cylindrocorpus Goodey is given.